From Leopard Gecko Wiki
Originally produced by Pat Murphy in 1991, the Murphy Patternless is a Leopard Gecko which lacks all pattern. As a hatchling, they will hatch with a lightly colored body with random tan, gray, or brown markings on the body. By the age of 10 months, the markings will have completely faded and the gecko's body color will vary between yellow and a deep purple. Throughout the generations, breeders have been able to incorporate the Carrot Tail into the Murphy Patternless Leopard Geckos. Marcia McGuiness from Golden Gate Geckos has a beautiful group of Murphy Patternless Carrot Tails.
Murphy Patternless Genetics
The Murphy Patternless trait is a simple recessive trait: if a Murphy Patternless is bred to a Normal Leopard Gecko, all of the hatchlings will be heterozygous for Murphy Patternless. If the hatchlings were to be bred back to each other, there would be a 25% chance of creating Murphy Patternless Leopard Geckos. Of the remaining offspring, there would be a 66.7% chance they would be heterozygous for Murphy Patternless.
Murphy Patternless Crosses
Aside from the Carrot Tail trait in the Murphy Patternless, there are many other crosses available. Shelly at Lizard Lair has crossed Murphy Patternless into her Mack Snow Leopard Geckos creating Mack Snow Murphy Patternless.
Murphy Patternless has also been crossed into all three albino strains; Bell, Tremper, and Rainwater. The first Murphy Patternless Bell Albino was recently produced by Pat Kline from Luxurious Leopards.
Another cross is with the Blizzard trait. A true Banana Blizzard is a Murphy Patternless Blizzard. Since there is no visual way to see if the gecko is both homozygous for Blizzard and Murphy Patternless, test breeding must be done to prove out the Leopard Gecko.